Cap plug



Juhe 25, 1929. L. BARNETT 1,718,518

' CAP PLUG Filed Feb. 8, 1927 l3 1/ 1 11 M /5 10 1/ m 206/: 30W 13 I N V EN TOR.

Patented June 25, 1929.

UNITED STATES I LOUIS BARNETT, OF BROOKLYN, NEW YORK.

CAI PLUG.

Application filed February 8, 1927. Serial No. 166,647.

This invention relates to interchangeable connecting devices for electric circuits and more particularly is directed to improvements in receptacle forms of cap-plugs for connecting portable electricappliances, lighting systems and the like apparatus to an electric power supply source.

An object of the invention is to provide an improved cap-plug of the character described comprising few and simple parts, which shallbe cheap to manufacture, form a rugged structure yet be neat in appearance, and practical and efficient to a high degree in-use.

. Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the features of construction, combinations of elements and arrangement of parts which will be exemplified in the construction hereinafter described and of which the scope of application will be indicated in the following claims.

In the accompanying drawing, in which is shown several of the various possible illustrative embodiments of this invention,

Fig. 1 is a front elevational view'of a detachable electric circuit connecting device including a receptacle form of cap-plug embodying the invention inserted between the parts of a standard two-piece attachment plug, the receptacle cap-plug being partly broken away to ex ose the interior construction.

igs. 2 and 3 are bottom and top plan views,

respectively, of the receptacle plug cap shown Referring in detail to the drawing, 10 denotes a receptacle plug cap embodying the invention adapted to be inserted into a baseboard, flush receptacle, fixture socket outlet or as shown in Fig. 1, connected to the screw plug portion of a standard circuit attachment fitting. The plug-cap 10 may comprlse a onepiece body ortion 11 formed of insulating material suc as porcelain, pheno-condensate products or the like substances and metallic current carrying portions 12. The latter may be secured in any suitable manner to the 1nsulating body portion 11 as by means of metallic eyelet-anchors 13 which preferably have an iilid 13 of each embedded in the body portion The current carrying portions 12 may comprlse terminal blades 14 extending outwardly from one side 11 of the body portion 11, and spring contact members 15. The latter may be of any suitable construction and extend into a pair of spaced, parallelly aligned socket openings 11 provided in said body portion. The openings 11 project down from a side 11. of the body portion forming a top fiat face for the cap 10. The side 11 of said body portion is opposite said side 11. The latter bein g fitted with a closure plate 30 forming the bottom flat face of the cap 10 which is parallelly disposed with respect to said top face.

The terminal blades 14 and contact member 15 have extension portions 14 and 15, respectively, whereby they are rigidl secured to the body portion by the overturn ends 13 of the eyelet anchors 13, as shown in Figs. 1 and 2. Each terminal blade 14 with its corresponding contact member 15 is thus electrically and mechanically united into a substantial unitary and integral structure. The contact member 15 extends slightly less than the entire length of the socket openings 11 to eliminate possible short circuits or injury to the user. If desired, each member 15 may be provided with a spring protuberance 15 adapted to releasably engage with a slot 20 in each of the terminal blades 20 of a connectin device, such as a standard plug cap 21. See Fig. 1.

For securing the the ends of conductor wires 17 to connect an electricappliance (not shown) to the current carryin portions 12, binding screws 16 are threade into the terminal extensions 14.

A dominant feature of the invention resides inthe novel construction of thecapplug 10 which permits simple molding operations for forming the body portion 11 whereby a handy and rugged yet neat, attractive appearing device is produced. As seen from Fig. 1, said construction provides for the socket openings 11 to extend in offset parallel relation with respect to the blades -14 so that the leading end of said cap blades 20 can be brought below the level of the extensions 14 in close proximity to the botom face 11, thus forming the body portion 11 of minimum thickness between'said top and bottom faces. The top face 11 which forms a mounting for the cap-plug 21 is positioned in displaced re- 'ing 11". Through said assage 11, the conductor wires 17 extend or connecting to the current carrying portions 12. The interior of the body portion is preferably formed with a hollow or cavity 11 for receiving the knotted end 17 of the conductor wires 17 thereby providin an efficient and practical strain'relief for t e terminal connections at the binding screws 16.

Where a plurality of circuits such as Christmas tree lighting outfits, or electric appliances are to be connected to one outlet of a power supply source, the receptacle cap-plug 10 is particularly useful since it provides a quick means for adding one or more circuits without requiring intermediate fitting. Another advantage following from the" offset relations of the terminal blades 14 with the contact members 15 is that a normal outward pulling strain on the conductor wires 18 of the top plug-cap will not be directly transmitted to the detachable connection of the blades on the bottom side of the cap but will rather tend to wedge the blades of the latter in their connected position thus minimizing the possibility of accidental disconnection of the circuit.

In using the invention, the receptacle capplug 10 is connected to the free ends of the conductor wires 17 through which electric power is to be supplied to an appliance, lighting device, etc. (not shown) and the terminal blades 14 thereof are inserted into anelectric power outlet in the well known manner. Other apparatus may successively be connected in circuit by simply plugging in the terminal blades 14'of its receptacle cap-plug into, the socket opening 11' of the receptacle cap-plug already connected in circuit to' contact with the members 15 as shown in Fig. 4.

From the drawing and description given above, it is seen that the cap-plug 10 is of simple construction and permits connecting a plurality of circuits to a single electric power outlet using either a standard cap-plug 21 as' shown in Fig. 1, or cap-plugs 10 as shown in Fig. 4. In either case, the freedom of movement of the conductor wires 17 is no way interfered with.

In Figs. 5, 6 and 7 are shown a modified construction embodying the invention. Here the receptacle cap-plug 110 comprises a onep1ece body portion 111 and current carrying parts 112 which include the terminal blades 114. The body portion 111 is provided with pairs of spaced socket openings 111 in which extend pa1rs of contact members 115 thus forming two receptacle outlets instead of' only one as in cap 10 described above. The passage 111 .in said body portion through which the conductor wires 117 extend for connecting with the current carrying parts 12 is disposed between said outlets.

The cap-plug 110 is particularly adapted to cooperate and connect with two standard cap plugs 21 as shown in Fig. 5. Thus for every plug 110 used, two cap-plugs 21 may be connected into a single circuit outlet without requiring the usual extra outlet receptacle fitting.

It will thus be seen that there is provided a device in which the several objects of this invention are achieved and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above-invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawing is t'o-be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters Patent: I

1. In combination with a flexible conductor wire adapted to be attached to a portable electricappliance, a device adapted to be in terposed between two conventional parts of a members projecting from said other face por- 2 tion perpendicular therefrom and in oflset relation to said sockets adapted to engage contact terminals in sockets of the plug unit of said separable fitting, and conducting strips electrically connecting the blade members 3 with corresponding contact terminals, said body having a passage laterally offset with respect to said sockets, said conductor wire pass ing through said passage and electrically connected to said strips, contact terminals and blade members, each contact terminal extending in a socket between said spaced face portions with a terminal end in close proximity to each of said face portions whereby said face portions are spaced apart substantially the distance of a projecting blade member.

2. In combination with a flexible conductor wire adapted to be attached to a portable electric appliance, a device adapted to be interposed between two conventional parts of i of recessed sockets extending perpendicular- 1y into said body, contact terminals disposed within said sockets adapted to receive the blades of conventional caps, blade members projecting from the other face portion and in offset relation to said pairs of sockets adapted to engage contact terminals in sockets of the plug unit of said separable fitting, and conductor strips electrically connecting the blade members with corresponding contact terminals, said body having a passage extending between said pair of sockets, said conductor wire passing through said passage and electrically connected to said strips, contact terminals and blade members, each contact terminal extending in a socket between said spaced face portions with a terminal end in close proximity to each of said face portions whereby said face portions are spaced apart substantially the distance of a projecting blade member.

3. A plug cap of the character described comprising a one-piece insulating body having a pair of parallelly spaced, flat sides, one of said sides having socket opening extending perpendicularly thereto into said body, current carrying spring contact members positioned in said openings, terminal blades having extensions connecting with said members, said blades having prong ends projecting from the other of said sides in offset parallel relation with respect to said members, said body having a passage adapted to receive a conductor wire adjacent said first mentioned side for connecting with said blades, said spring contact members extending from just short of the first mentioned side to beyond said extensions in close proximity to the last mentioned side whereby said flat sides are spaced apart substantially the distance of the projecting prong ends.

4. A plug cap of the character described comprising a one-piece insulating body having parallelly spaced, fiat face portions, one of said face portions having a plurality of pairs of spaced socket openings extending perpendicularly into the body, current carrying spring contact members positioned in said openings to provide receptacle outlets adapted to receive a plurality of standard plugcaps, and terminal blades having extensions connecting with said members, said blades having prong ends projecting from the other of said face portions, said body havin a passage extending between said pairs oF socket openings adapted to receive a conductor wire for connecting with said current carrying means and blades, said spring contact members extending from just short of the first mentioned face portion to close proximity to the last mentioned face portion adapted to permit forming said body of a thickness be tween said spaced face portions substantially the distance of the projecting prong ends.

In testimony whereof I aflix my signature.

LOUIS BARNETT. 

